We report the case of a 60-year-old man presenting in our emergency department with a 2-day history of right lower abdominal pain, nausea, vomiting and low-grade fever. Physical examination evocated mild pain with positive rebound tenderness in the right lower abdominal quadrant, and positive right costovertebral angle tenderness. Routine blood tests, abdominal X-rays were conclusive for perforation. At explorative laparotomy, a terminal ileal perforation due to mutton bone with localized peritonitis was found, and a resection and end-to-end anastomosis was performed. Histological examination confirmed the presence of a perforation caused by a piece of mutton bone of size 2.5  1.5 cm. Conclusions: Mutton bone ingestion should be taken into account in the evaluation of acute abdominal pain. A detailed patient’s history may be crucial for a correct diagnosis and treatment.

Keywords:

Mutton bone, ingestion, perforation, peritonitis

Introduction

Enteric perforation and tubercular perforation present the most common causes of terminal ileum perforation. Other causes are iatrogenic perforation, penetrating abdominal trauma and ingestion of foreign bodies. When animal bones, needles, toothpicks or other sharp pointed objects are ingested, the risk of perforation is even higher.

Mutton bone ingestion is a relatively rare event that may results in serious gut injuries with peritonitis, sepsis or even death.

Case Presentation

We report the case of a 60-year-old man who was referred to our emergency department with a 2-day history of right lower abdominal pain, nausea, vomiting and low- grade fever. His vital signs were normal, except for a central body temperature of 38°C. There was no history of previous abdominal surgery. Physical examination revealed mild pain with positive rebound tenderness in the right lower abdominal quadrant and positive right costovertebral angle tenderness. There was no evidence of intra-abdominal masses. Routine blood tests were normal except for a WBC count of 11,860/mm3with 84,6% neutrophils. On X-ray erect abdomen, pneumoperitoneum was seen (Fig. 1).

The patient underwent explorative laparotomy. At explorative laparotomy, a terminal ileal perforation due to mutton bone with localized peritonitis was found; resection and end-to-end anastomosis was performed. The patient made an uneventful recovery and was discharged on postoperative Day 7. The histological examination confirmed the presence of a transmural terminal ileum perforation with abscess caused by a mutton bone (Fig. 2).

Literature Review

There are more than 300 cases1 of bowel perforation caused by foreign bodies reported in the literature. Fish bones, chicken bones, mutton bones and dentures are the commonest objects followed by toothpicks and cocktail sticks.2-11 Male gender, mutton bone-crushing habit, accompanied by alcoholic drinks were the main risk factors associated with mutton bone ingestion. Perforation of the ailmentary tract occurred

in 80% of these patients; in one-third of them, the mutton bone had migrated into adjacent organs (liver, retroperitoneum, inferior vena cava, etc.). Figure 3 (a-d) depict the typical sites of mutton bone lodgement along the alimentary canal.

Discussion

Mutton bone ingestion is a medical emergency, since it leads to acute abdomen and gut perforation. Since, spontaneous elimination of these sharp foreign bodies through the gastrointestinal tract is unlikely, foreign body ingestion should be taken into account during the evaluation of acute abdominal pain. The clinical presentation may include frank peritonitis, localized abscess formation, enterovesical fistula, intestinal obstruction and intestinal hemorrhage.1,9 The correct diagnosis is very difficult because of the low sensitivity of diagnostic investigations. Endoscopy can be very helpful when the mutton bone is localized in the upper gastrointestinal tract.5

The CT scan may be able to identify the site of perforation and the extent of intra-abdominal inflammation either with or without abscess formation. Although, the diagnostic yield is quite low, upper gastrointestinal endoscopy and ultrasound examination may be recommended in asymptomatic patients who are aware of the mutton bone ingestion and seek medical advice. The most common site of perforation is the terminal ileum and colon, although an increased incidence of perforation has been reported in association with Meckel’s diverticulum, the appendix and diverticular disease.12-16 Perforation commonly occurs at the point of acute angulation and narrowing.

Treatment usually involves resection of bowel, although occasionally repair has been described.1,13 X-ray abdomen showing pneumoperitoneum, considering the presence of an acute abdomen, with evidence of peritonitis, the patient was scheduled for surgical exploration and required resection and anastomosis.

This case suggests that a potential cause of lethal hazard may be unknown to the patient, but most of all it emphasizes the difficulty of a correct diagnosis with the most widely used instrumental examination, as endoscopy, ultrasound or CT scan. Consent to publish the case was obtained from our patient prior to discharge. The patient allowed us to share his story and clinical images because he understood the importance of raising awareness among physicians on this unusual surgical entity.